A Survey on Service Composition Middleware in Pervasive Environments

The development of pervasive computing has put the light on a challenging problem: how to dynamically compose services in heterogeneous and highly changing environments? We propose a survey that defines the service composition as a sequence of four steps: the translation, the generation, the evaluation, and finally the execution. With this powerful and simple model we describe the major service composition middleware. Then, a classification of these service composition middleware according to pervasive requirements - interoperability, discoverability, adaptability, context awareness, QoS management, security, spontaneous management, and autonomous management - is given. The classification highlights what has been done and what remains to do to develop the service composition in pervasive environments

An executable service composition code automatic creation tool based on Petri net model

For Web services composition problem, this paper proposes an executable code creation algorithm to model Web services composition based on Petri net model, and develops an executable composition code automatic creation tool. This tool can achieve the automatic creation process from composition model to executable code, and more meaningfully makes it possible to analyze and validate composition process logically. Finally, experiment results have proven that the tool of this paper is feasible.This work is partially supported by National Natural Science Foundation of China under Grant No. 61173042 and 61105047, National Basic Research Program of P. R. China (973 Program) under Grant No. 2010CB328101, Program for New Century Excellent Talents in University under Grant No. NCET-10-0598, \Shu Guang" Project supported by Shanghai Municipal Education Commission and Shanghai Education Development Foundation under Grant No. 10SG23 and Shanghai Rising- Star Program under Grant No. 12QH1402300, Hong Kong, Macao and Taiwan Science and Technology Cooperation Program of China No. 2013DFM10100

Reo + mCRL2: A Framework for Model-Checking Dataflow in Service Compositions

The paradigm of service-oriented computing revolutionized the field of software engineering. According to this paradigm, new systems are composed of existing stand-alone services to support complex cross-organizational business processes. Correct communication of these services is not possible without a proper coordination mechanism. The Reo coordination language is a channel-based modeling language that introduces various types of channels and their composition rules. By composing Reo channels, one can specify Reo connectors that realize arbitrary complex behavioral protocols. Several formalisms have been introduced to give semantics to Reo. In their most basic form, they reflect service synchronization and dataflow constraints imposed by connectors. To ensure that the composed system behaves as intended, we need a wide range of automated verification tools to assist service composition designers. In this paper, we present our framework for the verification of Reo using the mCRL2 toolset. We unify our previous work on mapping various semantic models for Reo, namely, constraint automata, timed constraint automata, coloring semantics and the newly developed action constraint automata, to the process algebraic specification language of mCRL2, address the correctness of this mapping, discuss tool support, and present a detailed example that illustrates the use of Reo empowered with mCRL2 for the analysis of dataflow in service-based process models